Stability and reactivity of alkylidene dihydropyridines

• DOI: 10.1039/d4ob00200h
• Publication Date: 2024-05-07T13:59:17Z
• Authors: Matthew Puzhistky; Ekadashi Pradhan; Andrei Nikolaev; Tao Zeng; Dan Fishlock; Arturo Orellana
• Keywords: Reactivity

Alkylidene dihydropyridines (ADHPs) are electron-rich nucleophilic intermediates that can be readily prepared by dearomatization of 4-alkylpyridines using chloroformate reagents and mild base. Their stability reactivity tuned with the reagent used as evidenced NMR chemical shifts oxidation potentials. ADHPs ethyl, allyl trichloroethyl undergo decomposition under an oxygen atmosphere at different rates (ethyl > trichloroethyl), predominantly to corresponding 4-acylpyridine. The derived from benzyl stable towards oxidation, those phenyl hydrolyze readily.